This invention relates to a paperboard container for fluids and in particular to such a container where the fitment used to fill and empty the container is located at its top, and the container has a top rim that will accommodate drum handling devices.
Paperboard containers having flexible, liquid impervious liners are becoming more widely used as a substitute for steel drums. Not only are paperboard containers easily disposed of in an environmentally safe manner when their use is completed, they can be shipped unassembled at a much lower cost than steel drums. Such containers are disclosed in Nordstrom, U.S. Pat. Re. 33,128; Heaps, Jr. et al., U.S. Pat. No. 4,850,506; Heaps, Jr. et al., U.S. Pat. No. 4,771,917; and Croley, U.S. Pat. No. 4,421,253.
Prior art paperboard containers have two shortcomings which prevent their use as a substitute for steel drums in many applications. Thus, their acceptance has been limited. Many products, particularly petroleum products, are pumped out of steel drums by mounting a hand operated pump in the threaded hole located in the lid of the drum. Operation of this pump transmits substantial forces to the lid. With paperboard containers a plastic fitment, which is fluidly connected to the liner, opens out of the container to permit filling and emptying of the container. This fitment is attached to the container by a fitment lock. In prior art containers of this type neither the top of the container nor the fitment lock is capable of carrying the loads associated with the operation of a hand pump. As a result, the fitment exits through the side rather than through the top of the prior art containers.
A second shortcoming with paperboard containers that prevents their being fully accepted as a replacement for steel drums is that they do not have a rim at their top edge that can be engaged by drum handling implements. These implements, such as rocker dollies and drum handling carts, have forks which fit under the drum and a "beak" which engages the rim of the drum. When installed they become rigidly attached to the drum and facilitate its movement. With paperboard containers a rim which projects unprotected above the top of the container would be easily damaged and in the process possibly compromise the integrity of the container.
The subject invention overcomes the foregoing limitations and shortcomings of the prior art paperboard containers by providing an upright tubular shell that is covered at its bottom and contains a flexible impervious liner. The top of the container is enclosed by an inner cap and outer closure means which are separated from the inner cap. Located around the periphery of the closure means are openings that abut the sidewall of the shell. Since there is a space between the inner cap and closure means, the sidewall of the shell is exposed below these openings and can be engaged by drum handing implements. However, because the openings only exposed short segments of the sidewall, the majority of the sidewall remains protected by the closure means and the sidewall is not readily subject to damage. In addition, the two layers provided by the inner cap and closure means supports the sidewall against lateral loading imparted by the implement, and prevents the liner from being damaged by drum handling implements.
In a preferred embodiment the inner cap and closure means have aligned holes through which the fitment extends. A fitment lock located between the inner cap and closure means engages the fitment and prevents its movement.
In one embodiment the fitment lock is a piece of paperboard which is folded into several overlapping flaps. Some of the flaps contain a rectangular opening which snugly engages the locking portion of the fitment and prevents the fitment from moving in a direction parallel with the axis of its passageway. Other flaps contain circular openings which snugly engage the neck of the fitment and prevent the fitment from moving in a direction perpendicular with its axis. With this embodiment the fitment lock preferably is adhesively attached to both the inner cap and closure means. In another embodiment the fitment lock is a block of wood having a thickness equal to the height of the locking portion of the fitment and containing a rectangular slot that engages the locking portion of the fitment. In this embodiment the fitment lock may be adhesively attached only to the inner cap.
The invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings.